我使用Swift与iOS编程,我使用这段代码来移动UITextField,但它不起作用。我正确地调用了函数keyboardWillShow,但是文本字段没有移动。我正在使用自动布局。
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillShow:"), name:UIKeyboardWillShowNotification, object: nil);
NSNotificationCenter.defaultCenter().addObserver(self, selector: Selector("keyboardWillHide:"), name:UIKeyboardWillHideNotification, object: nil);
}
deinit {
NSNotificationCenter.defaultCenter().removeObserver(self);
}
func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
//let contentInsets = UIEdgeInsets(top: 0, left: 0, bottom: keyboardSize.height, right: 0)
var frame = self.ChatField.frame
frame.origin.y = frame.origin.y - keyboardSize.height + 167
self.chatField.frame = frame
println("asdasd")
}
}
我已采取以下方式:
当textfield superview为view时,这很有用
class AdminLoginViewController: UIViewController,
UITextFieldDelegate{
@IBOutlet weak var txtUserName: UITextField!
@IBOutlet weak var txtUserPassword: UITextField!
@IBOutlet weak var btnAdminLogin: UIButton!
private var activeField : UIView?
var param:String!
var adminUser : Admin? = nil
var kbHeight: CGFloat!
override func viewDidLoad()
{
self.addKeyBoardObserver()
self.addGestureForHideKeyBoard()
}
override func viewWillDisappear(animated: Bool) {
super.viewWillDisappear(animated)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
}
func addGestureForHideKeyBoard()
{
let tapGesture = UITapGestureRecognizer(target: self, action: Selector("hideKeyboard"))
tapGesture.cancelsTouchesInView = false
view.addGestureRecognizer(tapGesture)
}
func hideKeyboard() {
self.view.endEditing(true)
}
func addKeyBoardObserver(){
NSNotificationCenter.defaultCenter().addObserver(self, selector: "willChangeKeyboardFrame:",
name:UIKeyboardWillShowNotification, object: nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "willChangeKeyboardFrame:",
name:UIKeyboardWillHideNotification, object: nil)
}
func removeObserver(){
NSNotificationCenter.defaultCenter().removeObserver(self)
}
//MARK:- textfiled Delegate
func textFieldShouldBeginEditing(textField: UITextField) -> Bool
{
activeField = textField
return true
}
func textFieldShouldEndEditing(textField: UITextField) -> Bool
{
if activeField == textField
{
activeField = nil
}
return true
}
func textFieldShouldReturn(textField: UITextField) -> Bool {
if txtUserName == textField
{
txtUserPassword.becomeFirstResponder()
}
else if (textField == txtUserPassword)
{
self.btnAdminLoginAction(nil)
}
return true;
}
func willChangeKeyboardFrame(aNotification : NSNotification)
{
if self.activeField != nil && self.activeField!.isFirstResponder()
{
if let keyboardSize = (aNotification.userInfo![UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue()
{
let dy = (self.activeField?.superview?.convertRect((self.activeField?.frame)!, toView: view).origin.y)!
let height = (self.view.frame.size.height - keyboardSize.size.height)
if dy > height
{
var frame = self.view.frame
frame.origin.y = -((dy - height) + (self.activeField?.frame.size.height)! + 20)
self.view.frame = frame
}
}
}
else
{
var frame = self.view.frame
frame.origin.y = 0
self.view.frame = frame
}
} }
下面是一个简单的解决方案,其中文本字段有一个约束将其绑定到底部布局指南。它只是将键盘高度添加到约束常数中。
// This constraint ties the text field to the bottom layout guide
@IBOutlet var textFieldToBottomLayoutGuideConstraint: NSLayoutConstraint!
override func viewDidLoad() {
super.viewDidLoad()
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillShow:", name:UIKeyboardWillShowNotification, object: nil);
NSNotificationCenter.defaultCenter().addObserver(self, selector: "keyboardWillHide:", name:UIKeyboardWillHideNotification, object: nil);
}
func keyboardWillShow(sender: NSNotification) {
if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.textFieldToBottomLayoutGuideConstraint?.constant += keyboardSize.height
}
}
func keyboardWillHide(sender: NSNotification) {
if let keyboardSize = (sender.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.CGRectValue() {
self.textFieldToBottomLayoutGuideConstraint?.constant -= keyboardSize.height
}
}
我正在使用swift 4,我解决了这个问题,没有使用任何额外的底部约束,看我的代码在这里。这对我的案子很有帮助
1)在did load中添加通知观察者
override func viewDidLoad() {
super.viewDidLoad ()
setupManager ()
//加载视图后进行任何额外的设置。
addobserver (self, selector: #selector(self. keyboardwillshow), name: NSNotification.Name。对象:nil)
addobserver (self, selector: #selector(self. keyboardwillhide), name: NSNotification.Name。对象:nil)
}
2)删除通知观察者
Deinit {
NotificationCenter.default.removeObserver(self)
}
3)增加键盘显示/隐藏方法
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.frame.origin.y -= keyboardSize.height
self.view.layoutIfNeeded()
})
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
UIView.animate(withDuration: 0.1, animations: { () -> Void in
self.view.frame.origin.y += keyboardSize.height
self.view.layoutIfNeeded()
})
}
}
4)添加textfield delegate和touchesBegan方法。usefull用于在屏幕上的textfield外触摸时隐藏键盘
override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
view.endEditing(true)
}
我使用的Swift 4解决方案需要键盘大小。将serverStatusStackView替换为任何你关心的视图,例如:self.view:
deinit {
NotificationCenter.default.removeObserver(self)
}
@objc func keyboardWillShow(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
serverStatusStackView.frame.origin.y = keyboardSize.height * 2 - serverStatusStackView.frame.height
}
}
@objc func keyboardWillHide(notification: NSNotification) {
if let keyboardSize = (notification.userInfo?[UIKeyboardFrameBeginUserInfoKey] as? NSValue)?.cgRectValue {
serverStatusStackView.frame.origin.y += keyboardSize.height
}
}
override func viewDidLoad() {
super.viewDidLoad()
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillShow(notification:)), name: NSNotification.Name.UIKeyboardWillShow, object: nil)
NotificationCenter.default.addObserver(self, selector: #selector(keyboardWillHide(notification:)), name: NSNotification.Name.UIKeyboardWillHide, object: nil)
}